Hello Andrew
Do the few lines define Haskell expressions (functions or constants)
or are they something like a copyright notice (which you want the same
in all files)?
If they are functions, avoiding putting them in a module would seem a
bit dubious. Most people probably have their own collection of
'missing' functions from the Prelude that they share between their
projects, (of course everyone has different variations of 'missing'
functions...)
Best wishes
Stephen